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Johannes Kepler

Biding His Time

The New Astronomy

Kepler arrived at the Benatek observatory on February
4, 1600, and Tycho was pleased to see him – for Tycho needed Kepler
as much as Kepler needed Tycho. Kepler had come to Tycho hoping
that Tycho would share his observations of the stars and planets,
as Kepler needed the data to perfect his universe of perfect solids.
But Tycho was secretly hoping that Kepler would reconsider this
plan. Tycho had his own theory of how the universe was constructed.
He imagined that the sun revolved around the earth and the other
planets revolved around the sun. Tycho hoped that Kepler would
help him develop the system so Tycho could take his place among
the great names in astronomy.

If Kepler had been hoping for a new mentor, he must have
been sorely disappointed. Tycho treated Kepler like a family dog,
and not a particularly well-loved one. Tycho refused to pay Kepler
the salary he had been promised, refused to share any more observations with
him than were absolutely necessary, and forced Kepler to waste
his time writing attacks on Tycho's enemies. Their short relationship
was filled with bitterness and fighting. Several times Kepler left
the lab in anger, only to return days or weeks later begging Tycho's
forgiveness.

Kepler was trapped. In July of 1600, he was permanently expelled
from Gratz, along with the rest of the town's Protestants. Kepler
once again turned to Maestlin for help and, once again, Maestlin
declined. He did not respond to Kepler's letters for another five
years. It was a miserable moment for Kepler, but a fortunate one
for Tycho, as it meant that Kepler had nowhere else to turn.

Frustrated as he was about his relationship with Tycho,
once Kepler went to work in the lab, nothing could have distracted
him from the problem at hand. As the most junior member of the
staff, Kepler had been assigned to work on the orbit of Mars: the
trickiest and thus least desirable of the planetary orbits. Kepler
was undaunted, and even bet one of his colleagues that the task
would take him only a week. It eventually took him seven years
– it would be the most frustrating and most fruitful years of his
life.

Kepler and Tycho's relationship was short-lived. On October
13, 1601, Tycho went to a fancy dinner with the Baron Rosenberg
and a number of other members of upper crust society. As Kepler recorded,
Tycho was too polite to leave the table to use the bathroom, instead
putting an unhealthy amount of pressure on his bladder. According
to Kepler, this caused the infection that killed him less than
two weeks later.

Tycho's last words seemed directed at Kepler: "Let me
not seem to have lived in vain," he pleaded. But Tycho's pleas
fell on deaf ears; Kepler would not raise the Tychonic planetary
system to the glory that Tycho had hoped. Instead, Kepler finally
got a hold of Tycho's observations and used them to create a new
vision of the Copernican universe.

After Tycho's death, Kepler was appointed to his position
as Rudolph II's Imperial Mathematicus. This title carried prestige
and a salary, meaning that Kepler could finally afford to immerse
himself in his studies. He worked on the orbit of Mars for five
more years and then, when he was finally ready to publish, was
almost prevented from doing so by a petty family feud.

Kepler had based all his research on Tycho's observations
– the same observations that Tycho had so jealously guarded during
his lifetime. After Tycho's death, Kepler took advantage of his
access to the lab. Without asking anyone's permission, took the
observations for himself, reasoning that he was the only one who
could make good use of them. When Tycho's family realized this,
they went on the offensive. Led by the Junker Tengnagel, Tycho's
son-in-law and former assistant, the Brahe family tried every legal
strategy they could think of to gain control of the observational
data. As the Brahes had powerful connections at court, Kepler was
left at their mercy. The feud took four years to resolve, until,
in 1608, Tengnagel finally gave permission for the book to be published.
The Astronomia Nova was finally published in 1609;
it would be Kepler's most important work.